Table T6. Composition of gas from analyses of decomposed samples of gas hydrate, Holes 1250C, 1250D, and 1250F.
Core, section,
interval (cm)
Depth
(mbsf)
C1
(ppmv)
C2
(ppmv)
C3
(ppmv)
i-C4
(ppmv)
n-C4
(ppmv)
n-C5
(ppmv)
i-C6
(ppmv)
H2S
(ppmv)
CO2
(ppmv)
O2
(ppmv)
N2
(ppmv)
C1/C2
204-1250C-












1H-CC 1.39 977,550 840 8.3



1,550 244 40 701 1,163
1H-CC 1.39 557,737 504 8.7



426 380 47,529 183,768 1,107
2H-CC, 0 5.06 944,819 624 11.0 4.2



4,360 10,505 17,404 1,513
11H-3, 94 86.35 916,522 40.3





5,328 11,754 41,594 22,742
204-1250D-












1H-1, 100 1.00 829,572 624 17.1



1,198 628 24,874 118,566 1,329
1H-2, 14-17 1.33 731,754 633 4.5



456 1,007 34,866 153,405 1,156
1H-2, 14-17 1.33 553,749 538.4 9.8




1,678 30,220 137,375 1,029
1H-2, 14-17 1.33 796,716 673.4 7.5




2,871 201 7,644 1,183
10H-3, 53-84 78.01 795,474 17.5 97.2




4,013 452 12,298 45,456
204-1250F-












1H-1, 23 100.23 903,894 27





2,554 17,393 61,192 33,981

Notes: C1 = methane, C2 = ethane, C3 = propane, i-C4 = isobutane, n-C4 = normal butane, n-C5 = normal pentane, i-C6 = isohexane, H2S = hydrogen sulfide, CO2 = carbon dioxide, O2 = oxygen, N2 = nitrogen. Blank cells = below detection limit.